Roku 3 + proper local playback support = ???

Although I haven't bought the device yet, I've fallen in love with the Roku 3 lately, because of its hardware design, interface and wide support of online streaming services. Netflix, Spotify and (potentially) HBO are the ones I'm mainly interested in.

Yet, I can't over the fact that I also have a FLAC and MKV library that I might want to use in some cases. It'd be awesome to have one device that posesses the best of both worlds, but I increasingly have the impression that such a device doesn't exist.

Perhaps I should just buy the Roku 3 and buy a second device for local playback...

Anyway, I'd love to hear what you think! :)